/*
 * Copyright (C) 2014, 2016 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include "include/JavaScriptCore/jit/GPRInfo.h"

namespace JSC {

    struct VMEntryFrame;

    class ExecState;

    class VM;

    struct VMEntryRecord {
        /*
         * This record stored in a vmEntryTo{JavaScript,Host} allocated frame. It is allocated on the stack
         * after callee save registers where local variables would go.
         */
        VM *m_vm;
        ExecState *m_prevTopCallFrame;
        VMEntryFrame *m_prevTopVMEntryFrame;

#if ENABLE(JIT) && NUMBER_OF_CALLEE_SAVES_REGISTERS > 0
        intptr_t calleeSaveRegistersBuffer[NUMBER_OF_CALLEE_SAVES_REGISTERS];
#endif

        ExecState *prevTopCallFrame() { return m_prevTopCallFrame; }

        SUPPRESS_ASAN ExecState *unsafePrevTopCallFrame() { return m_prevTopCallFrame; }

        VMEntryFrame *prevTopVMEntryFrame() { return m_prevTopVMEntryFrame; }

        SUPPRESS_ASAN VMEntryFrame *unsafePrevTopVMEntryFrame() { return m_prevTopVMEntryFrame; }
    };

    extern "C" VMEntryRecord *vmEntryRecord(VMEntryFrame *);

    struct VMEntryFrame {
#if ENABLE(JIT) && NUMBER_OF_CALLEE_SAVES_REGISTERS > 0

        static ptrdiff_t vmEntryRecordOffset() {
            VMEntryFrame *fakeVMEntryFrame = reinterpret_cast<VMEntryFrame *>(0x1000);
            VMEntryRecord *record = vmEntryRecord(fakeVMEntryFrame);
            return static_cast<ptrdiff_t>(
                    reinterpret_cast<char *>(record) - reinterpret_cast<char *>(fakeVMEntryFrame));
        }

        static ptrdiff_t calleeSaveRegistersBufferOffset() {
            return vmEntryRecordOffset() + OBJECT_OFFSETOF(VMEntryRecord, calleeSaveRegistersBuffer);
        }

#endif
    };

} // namespace JSC
